染料敏化太陽能電池光電轉換效率受到電子傳遞速度以及電子與電解質中的I3-所產生之再結合反應的影響，本研究針對電子與電解質中的I3-所產生之再結合反應，建構出動力學方程式，利用I-V特性曲線、電池開環電壓對光源強度改變之回應、電池開環電壓對I3-濃度改變之回應和切斷光源後開環電壓衰退的實驗結果合併，可將式中的參數予以定量。藉由電解質中加入TBP可提升電池開環電壓(從0.489至0.706V)，以致光電轉換效率提升(從5.095至8.687%)，利用我們所建構的方式運用至此系統，說明TBP的加入造成導帶邊緣能量的平移，此平移的差異與實際電池開環電壓的差異甚為相同，證實此法所求得的參數可性度。
至於電子傳遞的部分，我們發展出一套以鈦酸鹽結構直接形成二氧化鈦奈米結晶顆粒的方式與一般使用溶膠凝膠法來製備的二氧化鈦奈米顆粒作比較，藉由此法形成的奈米顆粒用來製成電極薄膜可獲得純銳鈦礦相及氧空缺較少的二氧化鈦結晶，有利於電子在導帶上的傳遞，因此可得到較高的光電轉換效率，從IMPS(Intensity-Modulated Photocurrent Spectroscopy)分析的結果可證實具純銳鈦礦相與結晶缺陷少的二氧化鈦擁有較快的電子擴散速度。

Charge recombination between dye-sensitized TiO2 electrodes and I3- in the electrolyte and electron diffusion in the nanocrystalline TiO2 electrode govern the performance of a dye-sensitized solar cell (DSSC). The present work constructed a theoretical model to explore the recombination kinetics. The sensitizer was cis-di(thiocyanate)bis(2,2’-bipyridyl-4,4’-dicarboxylate) ruthenium (II). The photocurrent-voltage characteristics, the open-circuit voltage in response to light intensity, the open-circuit voltage in response to I3- concentration, and the open-circuit voltage decay behavior were combined to give the kinetic parameters for the recombination. This developed model was applied to cells with or without the presence of 4-tert-butylpyridine (TBP), which improved significantly the open-circuit voltage (from 0.489 to 0.706 V) and thus the cell conversion efficiency (from 5.095 to 8.687%). The promotion in the open-circuit voltage has been ascribed to the shift of the TiO2 conduction band edge due to TBP addition.
As to electron transfer, TiO2 electrodes made of colloids derived from a titanate-directed route and a conventional sol-gel synthesis were subjected to examination. The TiO2 electrode obtained from the titanate-directed route consisted of phase-pure anatase with a lower degree of oxygen vacancy, and gave a better performance for an DSSC. IMPS (Intensity-Modulated Photocurrent Spectroscopy) analysis showed a higher rate for electron diffusion in the phase-pure and structure intact anatase TiO2.

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